iokit/IOKit/IOLib.h

   1 /*
   2  * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * Copyright (c) 1998 Apple Computer, Inc.  All rights reserved.
  24  *
  25  * HISTORY
  26  *
  27  */
  28
  29 #ifndef __IOKIT_IOLIB_H
  30 #define __IOKIT_IOLIB_H
  31
  32 #ifndef KERNEL
  33 #error IOLib.h is for kernel use only
  34 #endif
  35
  36 #include <sys/appleapiopts.h>
  37
  38 #include <IOKit/system.h>
  39
  40 #include <IOKit/IOReturn.h>
  41 #include <IOKit/IOTypes.h>
  42 #include <IOKit/IOLocks.h>
  43
  44 #include <libkern/OSAtomic.h>
  45
  46 #ifdef __cplusplus
  47 extern "C" {
  48 #endif
  49
  50 #include <kern/thread_call.h>
  51 #include <kern/clock.h>
  52
  53 /*
  54  * min/max macros.
  55  */
  56
  57 #define min(a,b) ((a) < (b) ? (a) : (b))
  58 #define max(a,b) ((a) > (b) ? (a) : (b))
  59
  60 /*
  61  * These are opaque to the user.
  62  */
  63 typedef thread_t IOThread;
  64 typedef void (*IOThreadFunc)(void *argument);
  65
  66 /*
  67  * Memory allocation functions.
  68  */
  69
  70 /*! @function IOMalloc
  71     @abstract Allocates general purpose, wired memory in the kernel map.
  72     @discussion This is a general purpose utility to allocate memory in the kernel. There are no alignment guarantees given on the returned memory, and alignment may vary depending on the kernel configuration. This function may block and so should not be called from interrupt level or while a simple lock is held.
  73     @param size Size of the memory requested.
  74     @result Pointer to the allocated memory, or zero on failure. */
  75
  76 void * IOMalloc(vm_size_t size);
  77
  78 /*! @function IOFree
  79     @abstract Frees memory allocated with IOMalloc.
  80     @discussion This function frees memory allocated with IOMalloc, it may block and so should not be called from interrupt level or while a simple lock is held.
  81     @param address Pointer to the allocated memory.
  82     @param size Size of the memory allocated. */
  83
  84 void   IOFree(void * address, vm_size_t size);
  85
  86 /*! @function IOMallocAligned
  87     @abstract Allocates wired memory in the kernel map, with an alignment restriction.
  88     @discussion This is a utility to allocate memory in the kernel, with an alignment restriction which is specified as a byte count. This function may block and so should not be called from interrupt level or while a simple lock is held.
  89     @param size Size of the memory requested.
  90     @param alignment Byte count of the alignment for the memory. For example, pass 256 to get memory allocated at an address with bit 0-7 zero.
  91     @result Pointer to the allocated memory, or zero on failure. */
  92
  93 void * IOMallocAligned(vm_size_t size, vm_offset_t alignment);
  94
  95 /*! @function IOFreeAligned
  96     @abstract Frees memory allocated with IOMallocAligned.
  97     @discussion This function frees memory allocated with IOMallocAligned, it may block and so should not be called from interrupt level or while a simple lock is held.
  98     @param address Pointer to the allocated memory.
  99     @param size Size of the memory allocated. */
 100
 101 void   IOFreeAligned(void * address, vm_size_t size);
 102
 103 /*! @function IOMallocContiguous
 104     @abstract Allocates wired memory in the kernel map, with an alignment restriction and physically contiguous.
 105     @discussion This is a utility to allocate memory in the kernel, with an alignment restriction which is specified as a byte count, and will allocate only physically contiguous memory. The request may fail if memory is fragmented, and may cause large amounts of paging activity. This function may block and so should not be called from interrupt level or while a simple lock is held.
 106     @param size Size of the memory requested.
 107     @param alignment Byte count of the alignment for the memory. For example, pass 256 to get memory allocated at an address with bits 0-7 zero.
 108     @param physicalAddress IOMallocContiguous returns the physical address of the allocated memory here, if physicalAddress is a non-zero pointer.
 109     @result Virtual address of the allocated memory, or zero on failure. */
 110
 111 void * IOMallocContiguous(vm_size_t size, vm_size_t alignment,
 112                            IOPhysicalAddress * physicalAddress);
 113
 114 /*! @function IOFreeContiguous
 115     @abstract Frees memory allocated with IOMallocContiguous.
 116     @discussion This function frees memory allocated with IOMallocContiguous, it may block and so should not be called from interrupt level or while a simple lock is held.
 117     @param address Virtual address of the allocated memory.
 118     @param size Size of the memory allocated. */
 119
 120 void   IOFreeContiguous(void * address, vm_size_t size);
 121
 122
 123 /*! @function IOMallocPageable
 124     @abstract Allocates pageable memory in the kernel map.
 125     @discussion This is a utility to allocate pageable memory in the kernel. This function may block and so should not be called from interrupt level or while a simple lock is held.
 126     @param size Size of the memory requested.
 127     @param alignment Byte count of the alignment for the memory. For example, pass 256 to get memory allocated at an address with bits 0-7 zero.
 128     @result Pointer to the allocated memory, or zero on failure. */
 129
 130 void * IOMallocPageable(vm_size_t size, vm_size_t alignment);
 131
 132 /*! @function IOFreePageable
 133     @abstract Frees memory allocated with IOMallocPageable.
 134     @discussion This function frees memory allocated with IOMallocPageable, it may block and so should not be called from interrupt level or while a simple lock is held.
 135     @param address Virtual address of the allocated memory.
 136     @param size Size of the memory allocated. */
 137
 138 void IOFreePageable(void * address, vm_size_t size);
 139
 140 /*
 141  * Typed memory allocation macros. Both may block.
 142  */
 143 #define IONew(type,number)        (type*)IOMalloc(sizeof(type) * (number) )
 144 #define IODelete(ptr,type,number) IOFree( (ptr) , sizeof(type) * (number) )
 145
 146 /*! @function IOSetProcessorCacheMode
 147     @abstract Sets the processor cache mode for mapped memory.
 148     @discussion This function sets the cache mode of an already mapped & wired memory range. Note this may not be supported on I/O mappings or shared memory - it is far preferable to set the cache mode as mappings are created with the IOMemoryDescriptor::map method.
 149     @param task Task the memory is mapped into.
 150     @param address Virtual address of the memory.
 151     @param length Length of the range to set.
 152     @param cacheMode A constant from IOTypes.h, <br>
 153         kIOMapDefaultCache to inhibit the cache in I/O areas, kIOMapCopybackCache in general purpose RAM.<br>
 154         kIOMapInhibitCache, kIOMapWriteThruCache, kIOMapCopybackCache to set the appropriate caching.<br>
 155     @result An IOReturn code.*/
 156
 157 IOReturn IOSetProcessorCacheMode( task_t task, IOVirtualAddress address,
 158                                   IOByteCount length, IOOptionBits cacheMode );
 159
 160 /*! @function IOFlushProcessorCache
 161     @abstract Flushes the processor cache for mapped memory.
 162     @discussion This function flushes the processor cache of an already mapped memory range. Note in most cases it is preferable to use IOMemoryDescriptor::prepare and complete to manage cache coherency since they are aware of the architecture's requirements. Flushing the processor cache is not required for coherency in most situations.
 163     @param task Task the memory is mapped into.
 164     @param address Virtual address of the memory.
 165     @param length Length of the range to set.
 166     @result An IOReturn code. */
 167
 168 IOReturn IOFlushProcessorCache( task_t task, IOVirtualAddress address,
 169                                   IOByteCount length );
 170
 171 /*! @function IOThreadSelf
 172     @abstract Returns the osfmk identifier for the currently running thread.
 173     @discussion This function returns the current thread (a pointer to the currently active osfmk thread_shuttle). */
 174
 175 #define IOThreadSelf() (current_thread())
 176
 177 /*! @function IOCreateThread
 178     @abstract Create a kernel thread.
 179     @discussion This function creates a kernel thread, and passes the caller supplied argument to the new thread.
 180     @param function A C-function pointer where the thread will begin execution.
 181     @param argument Caller specified data to be passed to the new thread.
 182     @result An IOThread identifier for the new thread, equivalent to an osfmk thread_t. */
 183
 184 IOThread IOCreateThread(IOThreadFunc function, void *argument);
 185
 186 /*! @function IOExitThread
 187     @abstract Terminate exceution of current thread.
 188     @discussion This function destroys the currently running thread, and does not return. */
 189
 190 volatile void IOExitThread();
 191
 192 /*! @function IOSleep
 193     @abstract Sleep the calling thread for a number of milliseconds.
 194     @discussion This function blocks the calling thread for at least the number of specified milliseconds, giving time to other processes.
 195     @param milliseconds The integer number of milliseconds to wait. */
 196
 197 void IOSleep(unsigned milliseconds);
 198
 199 /*! @function IODelay
 200     @abstract Spin delay for a number of microseconds.
 201     @discussion This function spins to delay for at least the number of specified microseconds. Since the CPU is busy spinning no time is made available to other processes; this method of delay should be used only for short periods. Also, the AbsoluteTime based APIs of kern/clock.h provide finer grained and lower cost delays.
 202     @param microseconds The integer number of microseconds to spin wait. */
 203
 204 void IODelay(unsigned microseconds);
 205
 206 /*! @function IOLog
 207     @abstract Log a message to console in text mode, and /var/log/system.log.
 208     @discussion This function allows a driver to log diagnostic information to the screen during verbose boots, and to a log file found at /var/log/system.log. IOLog should not be called from interrupt context.
 209     @param format A printf() style format string (see printf() documentation).
 210     @param other arguments described by the format string. */
 211
 212 void IOLog(const char *format, ...)
 213 __attribute__((format(printf, 1, 2)));
 214
 215 void kprintf(const char *format, ...);
 216
 217 /*
 218  * Convert a integer constant (typically a #define or enum) to a string
 219  * via an array of IONamedValue.
 220  */
 221 const char *IOFindNameForValue(int value,
 222         const IONamedValue *namedValueArray);
 223
 224 /*
 225  * Convert a string to an int via an array of IONamedValue. Returns
 226  * kIOReturnSuccess of string found, else returns kIOReturnBadArgument.
 227  */
 228 IOReturn IOFindValueForName(const char *string,
 229         const IONamedValue *regValueArray,
 230         int *value);                            /* RETURNED */
 231
 232 /*! @function Debugger
 233     @abstract Enter the kernel debugger.
 234     @discussion This function freezes the kernel and enters the builtin debugger. It may not be possible to exit the debugger without a second machine.
 235     @param reason A C-string to describe why the debugger is being entered. */
 236
 237 void Debugger(const char * reason);
 238
 239 struct OSDictionary * IOBSDNameMatching( const char * name );
 240 struct OSDictionary * IOOFPathMatching( const char * path, char * buf, int maxLen );
 241
 242 /*
 243  * Convert between size and a power-of-two alignment.
 244  */
 245 IOAlignment IOSizeToAlignment(unsigned int size);
 246 unsigned int IOAlignmentToSize(IOAlignment align);
 247
 248 /*
 249  * Multiply and divide routines for IOFixed datatype.
 250  */
 251
 252 static inline IOFixed IOFixedMultiply(IOFixed a, IOFixed b)
 253 {
 254     return (IOFixed)((((SInt64) a) * ((SInt64) b)) >> 16);
 255 }
 256
 257 static inline IOFixed IOFixedDivide(IOFixed a, IOFixed b)
 258 {
 259     return (IOFixed)((((SInt64) a) << 16) / ((SInt64) b));
 260 }
 261
 262 /*
 263  * IORound and IOTrunc convenience functions, in the spirit
 264  * of vm's round_page() and trunc_page().
 265  */
 266 #define IORound(value,multiple) \
 267         ((((value) + (multiple) - 1) / (multiple)) * (multiple))
 268
 269 #define IOTrunc(value,multiple) \
 270         (((value) / (multiple)) * (multiple));
 271
 272
 273 #ifdef __APPLE_API_OBSOLETE
 274
 275 /* The following API is deprecated */
 276
 277 #undef eieio
 278 #define eieio() \
 279     OSSynchronizeIO()
 280
 281 void IOPanic(const char *reason);
 282
 283 /* The API exported by kern/clock.h
 284    should be used for high resolution timing. */
 285
 286 void IOGetTime( mach_timespec_t * clock_time);
 287
 288 extern mach_timespec_t IOZeroTvalspec;
 289
 290 #endif /* __APPLE_API_OBSOLETE */
 291
 292 #ifdef __cplusplus
 293 } /* extern "C" */
 294 #endif
 295
 296 #endif /* !__IOKIT_IOLIB_H */